• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.9
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• pp.1010-1019
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• 2008

In this paper, we present a noise analysis and measurement results of a bio-radar system that can detect human heartbeat and respiration signals. The noise analysis including various phase noise effects is very important in designing the bio-radar system, since the frequency difference between the received signal and local oscillator is very small and the received power is very low. All of the noise components in a bio-radar system are considered from the point of view of SNR. From this analysis, it can be concluded that the phase noise due to antenna leakage is a dominant factor and is a function of range correlation. Therefore, the phase noise component with range correlation effect, which is the most important noise contribution, is measured using the measurement setup and compared with the calculated results. From the measurement results, our measurement setup can measure a closed-in phase noise of a free-running oscillator. Based on these results, it is possible to design a 2.4 GHz bio-radar system quantitatively which has a detection range of 50 cm and low power of 1 mW without additional PLL circuits.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.4
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• pp.41-48
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• 2010

To improve the pot life of one-part in-house anisotropic conductive paste (ACP) formulations, 2-methyl imidazole curing accelerator powders were encapsulated with five agents. Through measuring the melting point of the five agents using DSC, it was confirmed that a encapsulation process with liquid-state agents is possible. Viscosity of ACP formulations containing the encapsulated imidazole powders was measured as a function of storage time from viscosity measurements. As a result, pot life of the formulations containing imidazole powders encapsulated with stearic acid and carnauba wax was improved, and these formulations indicated similar curing behaviors to a basic formulation containing rare imidazole. However, the bondlines made of these formulations exhibited low average shear strength values of about 37% level in comparison with the basic formulation.

• Journal of IKEEE
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• v.24 no.2
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• pp.378-384
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• 2020

The location information of the people or mover is essential for supporting various smart mobility services in railway stations which are mostly underground. For this purpose, a smart braille block is proposed to identify the location of the mover of the people. In this paper, the frequency characteristics of each material of the upper and lower parts of the braille block are analyzed to examine the appropriate materials for railway history. In addition, the guidelines for actual manufacturing were derived by analyzing the separation distance between two RF sensors in the smart braille block. As a result of analysis through the characteristic analysis in this paper, after selecting the material suitable for the construction site when the smart braille block is applied, the performance change of the RF system, especially the antenna that greatly influences the RF performance, must be reviewed in advance. It seems to have to be applied after checking through.